<!DOCTYPE html>
<html lang="en">
<head>
    <meta charset="UTF-8">
    <title>太极</title>
</head>
<style>
    html,body{
        overflow: hidden;
    }
    .div1{
        height: 200px;
        width: 0;
        border-left: 100px solid #fff;
        border-right: 100px solid #000;
        border-radius: 100%;
        position: absolute;
        top: 0;
        left: 0;
        bottom: 0;
        right: 0;
        margin: auto;
        box-shadow: 0 0 30px 10px rgba(225,0,255,.3);
        animation: a 5s linear infinite;
        animation-play-state: paused;
    }
    .div1::before{
        content: '';
        height: 100px;
        width: 100px;
        background: #000;
        border-radius: 50%;
        box-shadow: 0 100px 0 #fff;
        position: absolute;
        top:0;
        left:-50px;
    }
     .div1::after{
        content: '';
        height: 50px;
        width: 50px;
        background: #fff;
        border-radius: 50%;
        box-shadow: 0 100px 0 #000;
        position: absolute;
        top:25px;
        left:-25px;
    }
    @keyframes a{
        0%{
            transform: rotate(0deg);
        }
        100%{
            transform: rotate(360deg);
        }
    }
    .div1:hover{
        animation-play-state: running;
    }
</style>
<body>
    <div class="div1"></div>
</body>
</html>